1. Field of the Invention
The invention relates to a stop element for limiting the regulating distance of a longitudinal adjustment device for seats, especially motor vehicle seats, whose seat part is fastened on sliding rails, wherein each sliding rail is longitudinally slidable in a guide rail which is secured on the vehicle floor, wherein at least one sliding rail can be secured on the guide rail in selectable longitudinal positions by means of a locking device, wherein between the sliding rail and the guide rail the stop element is provided.
2. Description of the Related Art
From DE 196 47 448 a rail arrangement comprised of guide rails and sliding rails with integrated longitudinal adjustment device is known in which the sliding travel stroke between the sliding rail and the guide rail is limited in a conventional manner. In this context, the limitation is, for example, in the form of wall portions bent out of the rails and used as stop elements.
Moreover, it is conventional to provide bolts or similar components on the rails which serve as stop elements. Such stop elements are non-elastic so that relatively high forces act on the stop elements, resulting, in turn, in loud contact noise when the movable sliding rail suddenly impacts on the stop elements, especially when the sliding stroke is carried out vehemently and hard. Moreover, the manufacture of stop elements in the aforementioned manner requires additional process steps when manufacturing the guide rails and the sliding rails.
It is an object of the invention to provide a stop element between the guide rail and sliding rail which, on the one hand, is elastic and, on the other hand, does not require a preparatory manufacturing process on the rails. This object is solved by the stop element being comprised of an impact member, having a snap-in head extending through a penetration of the guide rail, and of a locking hook, penetrating this impact member and lockingly engaging the guide rail. Such a stop element comprised of an impact member and a locking member can be secured because of its two-part configuration by means of a locking hook in already present penetrations in the bottom of the guide rail, which penetrations form a tooth row for the locking device, so that a special manufacturing expenditure for the purpose of attaching the stop element is eliminated. Moreover, such a stop element can be produced of plastic material, wherein preferably an elastic, thermoplastic plastic material can be used for the impact member, while the locking hook may be formed of a high-strength and tenacious plastic material.
For fixation of the stop element on the guide rail, the impact member advantageously has a through hole, designed to be penetrated by the locking hook and extending to the edge portion of the snap-in head, while the lower portion of the locking hook has a design for complementing the snap-in head in the area of its through hole. In this connection, the impact member may have an approximately rectangular base surface with an impact tip pointing in the direction of the longitudinal axis and may have at its underside the snap-in head which fits into the penetration of the upwardly curved bottom of the guide rail, wherein the snap-in head is provided with locking projections pointing in the longitudinal direction of the guide rail and engaging the bottom of the guide rail from below.
For the purpose of a secure clamping of the impact member on the guide rail, the locking hook is provided at its upper side with a projection supported on a shoulder of the impact member and is provided at its underside with a locking projection complementing the locking projections of the snap-in head. In certain embodiments, the sliding rail itself, or its sliding cage, can impact on this secured stop element; however, it is also possible that the latch support receiving the locking device will come to rest on the stop element. In order to be able to safely support the stop element for the force uptake when the guide rail or its components impact, the impact member has support fingers at its reward portion remote from the impact tip which rest against the bottom of the guide rail. In this connection, the laterally projecting support fingers may each have an upwardly curved portion at their free ends which may be provided for realizing a contact surface for the ball retainer cages.